So the engine in the 380SL that I just bought (116.962) has a dual row chain? Its an Australian delivered car, but I believe these to have Euro-spec engines...Also keep in mind that the single row chain issue was for North American production vehicles. Euro versions of the 3.8L M116 had the double row from the beginning.
If you really want to be sure, you can take a flashlight and a small mirror, like a dental mirror, and angle it into the oil filler neck on the valve cover. With paitience and a bit of wiggling, you CAN see the chain and determine if it is a single row or double.
Don't despair if it's a single. The car has lasted over 25 years with it so plan on changing it every 40k or so. If your car is not a daily driver, you might not have to change it for another decade.
Alternatively, you can knock a hole in the valve cover to get the best possible view for conversion confirmation.OLD POST---I agree 100%! Forget changing it every 40k miles---do it at 20k intervals which will probably be 10yrs of driving!!
I've got an '80 450sl with 62,000 miles. Don't know if PO ever had any chain work done. Does this mean I don't have to worry about it or should I have my mech replace guides and chain?For model year 1981, Mercedes substituted a lighter, more efficient all-alloy 3.8 liter V-8 for the old reliable iron-block 4.5-liter V-8. And along with it came trouble.
The engine has a single-row timing chain, which as the miles piles on, tend to stretch. Unchecked, the chain can jump its sprockets, causing pistons to collide with valves, leaving the 380SL owner facing a $6,000 repair bill. During 1984, Mercedes switched to a double-row chain and solved the problem.
Though it was not an announced recall, Rugg says that at one time Mercedes did convert some of the early 380SLs, free of charge, to double row chain for some customers. "The only way to know if a car is converted is to take off the valve cover and look."
Converting one now is a $2500-$3000 proposition, said Marx. But Marx added that the conversion is unnecessary if the owner changes the chain and tensioner every 40,000 miles -- a $300 job.
Mercedes Benz 107 SL SLC Resource Center 280 280sl 350 350sl 380 380sl 420 420sl 450 450sl 500 500sl 560 560sl
Keep in mind this article and its prices are a bit outdated......
It's not the miles it is the years. The guides get brittle with age (and heat). One option is to pull one valve cover (four screws, the valve cover gasket is re-useable) and just look at the guides, if they are light color and new looking congratulations. Dark brown, cracks, wear from chain, etc. replace them now. May as well do new chain, cam sprockets, upper guides, chain tensioner, and plastic oilers all at once. No need to remove engine or fool with the lower guides or lower sprockets. On the 1980 the right cover is easier to remove than the left due to the routing of hoses. If you have a video inspection camera you might be able to bypass the valve cover removal, but IMHO it is better to open and inspect rather than video and guess.I've got an '80 450sl with 62,000 miles. Don't know if PO ever had any chain work done. Does this mean I don't have to worry about it or should I have my mech replace guides and chain?
Old rail color left, new rail color right. Many advocate using original MB parts. Search this board you will see much darker examples. Old sprocket left, hard to see wear in pic easier to see if superimposed. These SWAG sprockets were $20 each well worth the effort.Thanks for the info. Will pull that cover sometime this week and check it out.